1. Field of the Invention
The present invention relates to an action for a keyboard-based musical instrument which actuates in response to depression on an associated key to swing a hammer which in turn strikes a string.
2. Description of the Prior Art
An action for a keyboard-based musical instrument is configured to actuate in response to depression on an associated key to swing a hammer which in turn strikes a string. An action for a grand piano is comprised of action parts which include a wippen carried on a rear portion of a key for pivotal movement about the rear end of the key; a repetition lever pivotably attached to the wippen; a jack; and the like.
As the key is depressed from a free state, the wippen is pushed up, causing the repetition lever and jack to pivotally move together upward. Associated with the pivotal movements of these parts, the jack pushes up a hammer which in turn swing upward to strike a string disposed above the hammer.
In recent years, parts made of a synthetic resin are increasingly used for the action for a keyboard-based musical instrument. This is because the parts made of synthetic resin can be worked in a higher accuracy at a lower cost, as compared with those made of wood, and hardly change in dimensions and weight with environmental changes such as humidity.
However, when the above-mentioned conventional parts made of a synthetic resin are used for an action, the motion of the action causes the action parts to rub against one another to be readily charged, resulting in the generation of static electricity. Since the synthetic resin is an insulating material, the static electricity, once generated, generally remains as it is without going away. The static electricity attracts dust, motes and the like in the air to cause stains on the action parts. Particularly, in a region where the action is accommodated, a hammer felt rubs against a string to produce motes which make the action more susceptible to stains, malfunction, reduced lifetime, and the like.
The present invention has been made to solve the problem as mentioned above, and it is an object of the invention to provide an action for a keyboard-based musical instrument which is capable of preventing action parts made of a synthetic resin from being charged, thereby eliminating without fail stains due to dust and motes in the air attracted onto the action parts by the action of static electricity.
To achieve the above object, the present invention provides an action for a keyboard-based musical instrument, configured to actuate in response to depression on a key to generate sound. The action is characterized by comprising a plurality of action parts, at least one of which is made of a synthetic resin having electrical conductivity at least on a surface thereof.
This action for a keyboard-based musical instrument is configured to actuate in response to depression on a key, to swing the hammer, through the plurality of action parts, such that the hammer strikes the string. Since at least one of the plurality of action parts is made of a synthetic resin having electrical conductivity at least on a surface thereof, static electricity generated by the action parts rubbing against one another during the actuation of the action could be promptly removed, thereby preventing the action parts from being charged. This results in the prevention of the action parts from stains due to dust and motes in the air attracted by the static electricity. Consequently, the action according to the present invention can eliminate malfunctions and reduced lifetime.
Preferably, in the action for a keyboard-based musical instrument, the at least one action part is applied with an antistatic coating on the surface.
In this preferred embodiment of the action for a keyboard-based musical instrument, since the at least one action part is applied with an antistatic coating on the surface, the action parts can be prevented from being charged by removing static electricity along the electrically conductive surface. Therefore, the aforementioned effect of the present invention can be provided only by applying the antistatic coating, for example, on the surface of an ordinary synthetic resin which is not electrically conductive.
Preferably, in the action for a keyboard-based musical instrument, the at least one action part is applied with the antistatic coating by dipping.
In this preferred embodiment of the action for a keyboard-based musical instrument, since the antistatic coating is applied by dipping, the surface of the action part can be entirely coated with the antistatic coating without some portions left unpainted, unlike brushing, so that the charging can be prevented without fail. In addition, the antistatic coating can be applied more easily than with the brushing.
Preferably, in the action for a keyboard-based musical instrument, the plurality of action parts include at least one action part deposited with an electrically conductive metal on a surface thereof.
In this preferred embodiment of the action for a keyboard-based musical instrument, the charging can be prevented by the electrically conductive metal deposited on the surface of the at least one action part. In addition, since a drying step is not needed, as would be involved in applying the antistatic coating, the process required for the manufacturing can be reduced.
Preferably, in the action for a keyboard-based musical instrument, the at least one action part comprises a molding made of an electrically conductive synthetic resin.
In this preferred embodiment of the action for a keyboard-based musical instrument, since the at least one action part itself is made of the electrically conductive synthetic resin, the antistatic effect can be readily provided without the need for steps of applying an antistatic coating, depositing an electrically conductive metal, and the like after molding.
Preferably, in the action for a keyboard-based musical instrument, the at least one action part comprises a plurality of action parts coupled to each other through an electrically conductive joint, wherein at least one of the plurality of action parts coupled to each other through the joint is coupled to a grounding part.
In this preferred embodiment of the action for a keyboard-based musical instrument, since the joint between the plurality of action parts is electrically conductive, and the at least one action part is coupled to the grounding part, static electricity generated on one action part could be promptly removed to the grounding part through the joint and other action parts without fail, thereby ensuring the prevention of charged action parts.
Preferably, in the action for a keyboard-based musical instrument, the joint comprises a bushing cloth.
Generally, the action for a keyboard-based musical instrument includes a bushing cloth wound around a joint of action parts for preventing wear and noise. Therefore, according to this preferred embodiment of the action for a keyboard-based musical instrument, the existing bushing cloth can be utilized and provided with electrical conductivity to readily provide the foregoing effect of preventing the charging.
Preferably, in the action for a keyboard-based musical instrument, the bushing cloth is impregnated with an antistatic agent.
In this preferred embodiment of the action for a keyboard-based musical instrument, the electrical conductivity can be readily ensured for the bushing cloth by impregnating the bushing cloth with the antistatic agent.
Preferably, in the action for a keyboard-based musical instrument, the bushing cloth is made of an electrically conductive fiber.
In this preferred embodiment of the action for a keyboard-based musical instrument, since the bushing cloth itself is made of an electrically conductive fiber, the electrical conductivity can be ensured for the bushing cloth without the need for impregnation of antistatic agent.